1. Field of the Invention
This invention pertains generally to the field of material dispensing equipment and more particularly to equipment for holding and discharging construction filler materials into trenches.
2. Description of the Prior Art
It is common practice when laying sewer lines or piping in trenches to provide a bedding of gravel or crushed rock for the pipes. Back filling of piping in trenches with sand, gravel, or crushed rock is also common to provide satisfactory drainage around the pipe and additional solid structural support thereto.
It is preferred that a fairly even layer of gravel or rock be laid under the pipe before the pipe has been emplaced in the trench, and that a further uniform layer of gravel or rock be placed around the pipe before the trench is filled. This has commonly been accomplished by manual shoveling of the stone or gravel into the trench, or by the use of a power shovel or "backhoe" which scoops a load of the filler material from an adjacent pile and delivers this material into the trench where it is dumped. Generally, substantial additional hand leveling and spreading of the material in the trench is required. A substantial portion of the filler material is lost in transferring the material from the pile, where it has been dumped by a supply truck, to the trench, because of the inevitable spillage that occurs when such loose flowing material is carried over either by hand or by a power shovel. The power shovel bucket also tends to disperse the filler material as it scoops into it. High quality filler material such as gravel and crushed rock is relatively expensive, and the loss of this material by dispersal as described above adds significantly to the cost of construction.
Where precise placement of the filler material in the trench is not essential, a front end loader type of tractor is sometimes utilized to simply scoop up a load of filler material, and deposit it into the trench in the proper place. However, this method of providing filling and bedding material to the trench is often not feasible because of the danger of driving the front end loader too close to the side walls of the trench and collapsing the walls. Generally, the end loader tractor simply deposits the filling material at the side of the trench, from where it is manually shoveled into the trench. A substantial portion of the filler material is also lost by this method because it is scattered on the ground at the sides of the trench.